189141ca4e0513c8775a70f8c125777ff410fbbc
[linux-2.6.git] / drivers / usb / class / cdc-wdm.c
1 /*
2  * cdc-wdm.c
3  *
4  * This driver supports USB CDC WCM Device Management.
5  *
6  * Copyright (c) 2007-2009 Oliver Neukum
7  *
8  * Some code taken from cdc-acm.c
9  *
10  * Released under the GPLv2.
11  *
12  * Many thanks to Carl Nordbeck
13  */
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/slab.h>
17 #include <linux/module.h>
18 #include <linux/mutex.h>
19 #include <linux/uaccess.h>
20 #include <linux/bitops.h>
21 #include <linux/poll.h>
22 #include <linux/usb.h>
23 #include <linux/usb/cdc.h>
24 #include <asm/byteorder.h>
25 #include <asm/unaligned.h>
26
27 /*
28  * Version Information
29  */
30 #define DRIVER_VERSION "v0.03"
31 #define DRIVER_AUTHOR "Oliver Neukum"
32 #define DRIVER_DESC "USB Abstract Control Model driver for USB WCM Device Management"
33
34 static const struct usb_device_id wdm_ids[] = {
35         {
36                 .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS |
37                                  USB_DEVICE_ID_MATCH_INT_SUBCLASS,
38                 .bInterfaceClass = USB_CLASS_COMM,
39                 .bInterfaceSubClass = USB_CDC_SUBCLASS_DMM
40         },
41         { }
42 };
43
44 MODULE_DEVICE_TABLE (usb, wdm_ids);
45
46 #define WDM_MINOR_BASE  176
47
48
49 #define WDM_IN_USE              1
50 #define WDM_DISCONNECTING       2
51 #define WDM_RESULT              3
52 #define WDM_READ                4
53 #define WDM_INT_STALL           5
54 #define WDM_POLL_RUNNING        6
55 #define WDM_RESPONDING          7
56 #define WDM_SUSPENDING          8
57
58 #define WDM_MAX                 16
59
60
61 static DEFINE_MUTEX(wdm_mutex);
62
63 /* --- method tables --- */
64
65 struct wdm_device {
66         u8                      *inbuf; /* buffer for response */
67         u8                      *outbuf; /* buffer for command */
68         u8                      *sbuf; /* buffer for status */
69         u8                      *ubuf; /* buffer for copy to user space */
70
71         struct urb              *command;
72         struct urb              *response;
73         struct urb              *validity;
74         struct usb_interface    *intf;
75         struct usb_ctrlrequest  *orq;
76         struct usb_ctrlrequest  *irq;
77         spinlock_t              iuspin;
78
79         unsigned long           flags;
80         u16                     bufsize;
81         u16                     wMaxCommand;
82         u16                     wMaxPacketSize;
83         u16                     bMaxPacketSize0;
84         __le16                  inum;
85         int                     reslength;
86         int                     length;
87         int                     read;
88         int                     count;
89         dma_addr_t              shandle;
90         dma_addr_t              ihandle;
91         struct mutex            lock;
92         wait_queue_head_t       wait;
93         struct work_struct      rxwork;
94         int                     werr;
95         int                     rerr;
96 };
97
98 static struct usb_driver wdm_driver;
99
100 /* --- callbacks --- */
101 static void wdm_out_callback(struct urb *urb)
102 {
103         struct wdm_device *desc;
104         desc = urb->context;
105         spin_lock(&desc->iuspin);
106         desc->werr = urb->status;
107         spin_unlock(&desc->iuspin);
108         clear_bit(WDM_IN_USE, &desc->flags);
109         kfree(desc->outbuf);
110         wake_up(&desc->wait);
111 }
112
113 static void wdm_in_callback(struct urb *urb)
114 {
115         struct wdm_device *desc = urb->context;
116         int status = urb->status;
117
118         spin_lock(&desc->iuspin);
119         clear_bit(WDM_RESPONDING, &desc->flags);
120
121         if (status) {
122                 switch (status) {
123                 case -ENOENT:
124                         dev_dbg(&desc->intf->dev,
125                                 "nonzero urb status received: -ENOENT");
126                         goto skip_error;
127                 case -ECONNRESET:
128                         dev_dbg(&desc->intf->dev,
129                                 "nonzero urb status received: -ECONNRESET");
130                         goto skip_error;
131                 case -ESHUTDOWN:
132                         dev_dbg(&desc->intf->dev,
133                                 "nonzero urb status received: -ESHUTDOWN");
134                         goto skip_error;
135                 case -EPIPE:
136                         dev_err(&desc->intf->dev,
137                                 "nonzero urb status received: -EPIPE\n");
138                         break;
139                 default:
140                         dev_err(&desc->intf->dev,
141                                 "Unexpected error %d\n", status);
142                         break;
143                 }
144         }
145
146         desc->rerr = status;
147         desc->reslength = urb->actual_length;
148         memmove(desc->ubuf + desc->length, desc->inbuf, desc->reslength);
149         desc->length += desc->reslength;
150 skip_error:
151         wake_up(&desc->wait);
152
153         set_bit(WDM_READ, &desc->flags);
154         spin_unlock(&desc->iuspin);
155 }
156
157 static void wdm_int_callback(struct urb *urb)
158 {
159         int rv = 0;
160         int status = urb->status;
161         struct wdm_device *desc;
162         struct usb_ctrlrequest *req;
163         struct usb_cdc_notification *dr;
164
165         desc = urb->context;
166         req = desc->irq;
167         dr = (struct usb_cdc_notification *)desc->sbuf;
168
169         if (status) {
170                 switch (status) {
171                 case -ESHUTDOWN:
172                 case -ENOENT:
173                 case -ECONNRESET:
174                         return; /* unplug */
175                 case -EPIPE:
176                         set_bit(WDM_INT_STALL, &desc->flags);
177                         dev_err(&desc->intf->dev, "Stall on int endpoint\n");
178                         goto sw; /* halt is cleared in work */
179                 default:
180                         dev_err(&desc->intf->dev,
181                                 "nonzero urb status received: %d\n", status);
182                         break;
183                 }
184         }
185
186         if (urb->actual_length < sizeof(struct usb_cdc_notification)) {
187                 dev_err(&desc->intf->dev, "wdm_int_callback - %d bytes\n",
188                         urb->actual_length);
189                 goto exit;
190         }
191
192         switch (dr->bNotificationType) {
193         case USB_CDC_NOTIFY_RESPONSE_AVAILABLE:
194                 dev_dbg(&desc->intf->dev,
195                         "NOTIFY_RESPONSE_AVAILABLE received: index %d len %d",
196                         dr->wIndex, dr->wLength);
197                 break;
198
199         case USB_CDC_NOTIFY_NETWORK_CONNECTION:
200
201                 dev_dbg(&desc->intf->dev,
202                         "NOTIFY_NETWORK_CONNECTION %s network",
203                         dr->wValue ? "connected to" : "disconnected from");
204                 goto exit;
205         default:
206                 clear_bit(WDM_POLL_RUNNING, &desc->flags);
207                 dev_err(&desc->intf->dev,
208                         "unknown notification %d received: index %d len %d\n",
209                         dr->bNotificationType, dr->wIndex, dr->wLength);
210                 goto exit;
211         }
212
213         req->bRequestType = (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE);
214         req->bRequest = USB_CDC_GET_ENCAPSULATED_RESPONSE;
215         req->wValue = 0;
216         req->wIndex = desc->inum;
217         req->wLength = cpu_to_le16(desc->wMaxCommand);
218
219         usb_fill_control_urb(
220                 desc->response,
221                 interface_to_usbdev(desc->intf),
222                 /* using common endpoint 0 */
223                 usb_rcvctrlpipe(interface_to_usbdev(desc->intf), 0),
224                 (unsigned char *)req,
225                 desc->inbuf,
226                 desc->wMaxCommand,
227                 wdm_in_callback,
228                 desc
229         );
230         desc->response->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
231         spin_lock(&desc->iuspin);
232         clear_bit(WDM_READ, &desc->flags);
233         set_bit(WDM_RESPONDING, &desc->flags);
234         if (!test_bit(WDM_DISCONNECTING, &desc->flags)
235                 && !test_bit(WDM_SUSPENDING, &desc->flags)) {
236                 rv = usb_submit_urb(desc->response, GFP_ATOMIC);
237                 dev_dbg(&desc->intf->dev, "%s: usb_submit_urb %d",
238                         __func__, rv);
239         }
240         spin_unlock(&desc->iuspin);
241         if (rv < 0) {
242                 clear_bit(WDM_RESPONDING, &desc->flags);
243                 if (rv == -EPERM)
244                         return;
245                 if (rv == -ENOMEM) {
246 sw:
247                         rv = schedule_work(&desc->rxwork);
248                         if (rv)
249                                 dev_err(&desc->intf->dev,
250                                         "Cannot schedule work\n");
251                 }
252         }
253 exit:
254         rv = usb_submit_urb(urb, GFP_ATOMIC);
255         if (rv)
256                 dev_err(&desc->intf->dev,
257                         "%s - usb_submit_urb failed with result %d\n",
258                         __func__, rv);
259
260 }
261
262 static void kill_urbs(struct wdm_device *desc)
263 {
264         /* the order here is essential */
265         usb_kill_urb(desc->command);
266         usb_kill_urb(desc->validity);
267         usb_kill_urb(desc->response);
268 }
269
270 static void free_urbs(struct wdm_device *desc)
271 {
272         usb_free_urb(desc->validity);
273         usb_free_urb(desc->response);
274         usb_free_urb(desc->command);
275 }
276
277 static void cleanup(struct wdm_device *desc)
278 {
279         usb_buffer_free(interface_to_usbdev(desc->intf),
280                         desc->wMaxPacketSize,
281                         desc->sbuf,
282                         desc->validity->transfer_dma);
283         usb_buffer_free(interface_to_usbdev(desc->intf),
284                         desc->wMaxCommand,
285                         desc->inbuf,
286                         desc->response->transfer_dma);
287         kfree(desc->orq);
288         kfree(desc->irq);
289         kfree(desc->ubuf);
290         free_urbs(desc);
291         kfree(desc);
292 }
293
294 static ssize_t wdm_write
295 (struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
296 {
297         u8 *buf;
298         int rv = -EMSGSIZE, r, we;
299         struct wdm_device *desc = file->private_data;
300         struct usb_ctrlrequest *req;
301
302         if (count > desc->wMaxCommand)
303                 count = desc->wMaxCommand;
304
305         spin_lock_irq(&desc->iuspin);
306         we = desc->werr;
307         desc->werr = 0;
308         spin_unlock_irq(&desc->iuspin);
309         if (we < 0)
310                 return -EIO;
311
312         desc->outbuf = buf = kmalloc(count, GFP_KERNEL);
313         if (!buf) {
314                 rv = -ENOMEM;
315                 goto outnl;
316         }
317
318         r = copy_from_user(buf, buffer, count);
319         if (r > 0) {
320                 kfree(buf);
321                 rv = -EFAULT;
322                 goto outnl;
323         }
324
325         /* concurrent writes and disconnect */
326         r = mutex_lock_interruptible(&desc->lock);
327         rv = -ERESTARTSYS;
328         if (r) {
329                 kfree(buf);
330                 goto outnl;
331         }
332
333         if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
334                 kfree(buf);
335                 rv = -ENODEV;
336                 goto outnp;
337         }
338
339         r = usb_autopm_get_interface(desc->intf);
340         if (r < 0) {
341                 kfree(buf);
342                 goto outnp;
343         }
344
345         if (!file->f_flags && O_NONBLOCK)
346                 r = wait_event_interruptible(desc->wait, !test_bit(WDM_IN_USE,
347                                                                 &desc->flags));
348         else
349                 if (test_bit(WDM_IN_USE, &desc->flags))
350                         r = -EAGAIN;
351         if (r < 0) {
352                 kfree(buf);
353                 goto out;
354         }
355
356         req = desc->orq;
357         usb_fill_control_urb(
358                 desc->command,
359                 interface_to_usbdev(desc->intf),
360                 /* using common endpoint 0 */
361                 usb_sndctrlpipe(interface_to_usbdev(desc->intf), 0),
362                 (unsigned char *)req,
363                 buf,
364                 count,
365                 wdm_out_callback,
366                 desc
367         );
368
369         req->bRequestType = (USB_DIR_OUT | USB_TYPE_CLASS |
370                              USB_RECIP_INTERFACE);
371         req->bRequest = USB_CDC_SEND_ENCAPSULATED_COMMAND;
372         req->wValue = 0;
373         req->wIndex = desc->inum;
374         req->wLength = cpu_to_le16(count);
375         set_bit(WDM_IN_USE, &desc->flags);
376
377         rv = usb_submit_urb(desc->command, GFP_KERNEL);
378         if (rv < 0) {
379                 kfree(buf);
380                 clear_bit(WDM_IN_USE, &desc->flags);
381                 dev_err(&desc->intf->dev, "Tx URB error: %d\n", rv);
382         } else {
383                 dev_dbg(&desc->intf->dev, "Tx URB has been submitted index=%d",
384                         req->wIndex);
385         }
386 out:
387         usb_autopm_put_interface(desc->intf);
388 outnp:
389         mutex_unlock(&desc->lock);
390 outnl:
391         return rv < 0 ? rv : count;
392 }
393
394 static ssize_t wdm_read
395 (struct file *file, char __user *buffer, size_t count, loff_t *ppos)
396 {
397         int rv, cntr = 0;
398         int i = 0;
399         struct wdm_device *desc = file->private_data;
400
401
402         rv = mutex_lock_interruptible(&desc->lock); /*concurrent reads */
403         if (rv < 0)
404                 return -ERESTARTSYS;
405
406         if (desc->length == 0) {
407                 desc->read = 0;
408 retry:
409                 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
410                         rv = -ENODEV;
411                         goto err;
412                 }
413                 i++;
414                 if (file->f_flags & O_NONBLOCK) {
415                         if (!test_bit(WDM_READ, &desc->flags)) {
416                                 rv = cntr ? cntr : -EAGAIN;
417                                 goto err;
418                         }
419                         rv = 0;
420                 } else {
421                         rv = wait_event_interruptible(desc->wait,
422                                 test_bit(WDM_READ, &desc->flags));
423                 }
424
425                 /* may have happened while we slept */
426                 if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
427                         rv = -ENODEV;
428                         goto err;
429                 }
430                 usb_mark_last_busy(interface_to_usbdev(desc->intf));
431                 if (rv < 0) {
432                         rv = -ERESTARTSYS;
433                         goto err;
434                 }
435
436                 spin_lock_irq(&desc->iuspin);
437
438                 if (desc->rerr) { /* read completed, error happened */
439                         desc->rerr = 0;
440                         spin_unlock_irq(&desc->iuspin);
441                         rv = -EIO;
442                         goto err;
443                 }
444                 /*
445                  * recheck whether we've lost the race
446                  * against the completion handler
447                  */
448                 if (!test_bit(WDM_READ, &desc->flags)) { /* lost race */
449                         spin_unlock_irq(&desc->iuspin);
450                         goto retry;
451                 }
452                 if (!desc->reslength) { /* zero length read */
453                         spin_unlock_irq(&desc->iuspin);
454                         goto retry;
455                 }
456                 clear_bit(WDM_READ, &desc->flags);
457                 spin_unlock_irq(&desc->iuspin);
458         }
459
460         cntr = count > desc->length ? desc->length : count;
461         rv = copy_to_user(buffer, desc->ubuf, cntr);
462         if (rv > 0) {
463                 rv = -EFAULT;
464                 goto err;
465         }
466
467         for (i = 0; i < desc->length - cntr; i++)
468                 desc->ubuf[i] = desc->ubuf[i + cntr];
469
470         desc->length -= cntr;
471         /* in case we had outstanding data */
472         if (!desc->length)
473                 clear_bit(WDM_READ, &desc->flags);
474         rv = cntr;
475
476 err:
477         mutex_unlock(&desc->lock);
478         return rv;
479 }
480
481 static int wdm_flush(struct file *file, fl_owner_t id)
482 {
483         struct wdm_device *desc = file->private_data;
484
485         wait_event(desc->wait, !test_bit(WDM_IN_USE, &desc->flags));
486         if (desc->werr < 0)
487                 dev_err(&desc->intf->dev, "Error in flush path: %d\n",
488                         desc->werr);
489
490         return desc->werr;
491 }
492
493 static unsigned int wdm_poll(struct file *file, struct poll_table_struct *wait)
494 {
495         struct wdm_device *desc = file->private_data;
496         unsigned long flags;
497         unsigned int mask = 0;
498
499         spin_lock_irqsave(&desc->iuspin, flags);
500         if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
501                 mask = POLLERR;
502                 spin_unlock_irqrestore(&desc->iuspin, flags);
503                 goto desc_out;
504         }
505         if (test_bit(WDM_READ, &desc->flags))
506                 mask = POLLIN | POLLRDNORM;
507         if (desc->rerr || desc->werr)
508                 mask |= POLLERR;
509         if (!test_bit(WDM_IN_USE, &desc->flags))
510                 mask |= POLLOUT | POLLWRNORM;
511         spin_unlock_irqrestore(&desc->iuspin, flags);
512
513         poll_wait(file, &desc->wait, wait);
514
515 desc_out:
516         return mask;
517 }
518
519 static int wdm_open(struct inode *inode, struct file *file)
520 {
521         int minor = iminor(inode);
522         int rv = -ENODEV;
523         struct usb_interface *intf;
524         struct wdm_device *desc;
525
526         mutex_lock(&wdm_mutex);
527         intf = usb_find_interface(&wdm_driver, minor);
528         if (!intf)
529                 goto out;
530
531         desc = usb_get_intfdata(intf);
532         if (test_bit(WDM_DISCONNECTING, &desc->flags))
533                 goto out;
534         file->private_data = desc;
535
536         rv = usb_autopm_get_interface(desc->intf);
537         if (rv < 0) {
538                 dev_err(&desc->intf->dev, "Error autopm - %d\n", rv);
539                 goto out;
540         }
541         intf->needs_remote_wakeup = 1;
542
543         mutex_lock(&desc->lock);
544         if (!desc->count++) {
545                 rv = usb_submit_urb(desc->validity, GFP_KERNEL);
546                 if (rv < 0) {
547                         desc->count--;
548                         dev_err(&desc->intf->dev,
549                                 "Error submitting int urb - %d\n", rv);
550                 }
551         } else {
552                 rv = 0;
553         }
554         mutex_unlock(&desc->lock);
555         usb_autopm_put_interface(desc->intf);
556 out:
557         mutex_unlock(&wdm_mutex);
558         return rv;
559 }
560
561 static int wdm_release(struct inode *inode, struct file *file)
562 {
563         struct wdm_device *desc = file->private_data;
564
565         mutex_lock(&wdm_mutex);
566         mutex_lock(&desc->lock);
567         desc->count--;
568         mutex_unlock(&desc->lock);
569
570         if (!desc->count) {
571                 dev_dbg(&desc->intf->dev, "wdm_release: cleanup");
572                 kill_urbs(desc);
573                 if (!test_bit(WDM_DISCONNECTING, &desc->flags))
574                         desc->intf->needs_remote_wakeup = 0;
575         }
576         mutex_unlock(&wdm_mutex);
577         return 0;
578 }
579
580 static const struct file_operations wdm_fops = {
581         .owner =        THIS_MODULE,
582         .read =         wdm_read,
583         .write =        wdm_write,
584         .open =         wdm_open,
585         .flush =        wdm_flush,
586         .release =      wdm_release,
587         .poll =         wdm_poll
588 };
589
590 static struct usb_class_driver wdm_class = {
591         .name =         "cdc-wdm%d",
592         .fops =         &wdm_fops,
593         .minor_base =   WDM_MINOR_BASE,
594 };
595
596 /* --- error handling --- */
597 static void wdm_rxwork(struct work_struct *work)
598 {
599         struct wdm_device *desc = container_of(work, struct wdm_device, rxwork);
600         unsigned long flags;
601         int rv;
602
603         spin_lock_irqsave(&desc->iuspin, flags);
604         if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
605                 spin_unlock_irqrestore(&desc->iuspin, flags);
606         } else {
607                 spin_unlock_irqrestore(&desc->iuspin, flags);
608                 rv = usb_submit_urb(desc->response, GFP_KERNEL);
609                 if (rv < 0 && rv != -EPERM) {
610                         spin_lock_irqsave(&desc->iuspin, flags);
611                         if (!test_bit(WDM_DISCONNECTING, &desc->flags))
612                                 schedule_work(&desc->rxwork);
613                         spin_unlock_irqrestore(&desc->iuspin, flags);
614                 }
615         }
616 }
617
618 /* --- hotplug --- */
619
620 static int wdm_probe(struct usb_interface *intf, const struct usb_device_id *id)
621 {
622         int rv = -EINVAL;
623         struct usb_device *udev = interface_to_usbdev(intf);
624         struct wdm_device *desc;
625         struct usb_host_interface *iface;
626         struct usb_endpoint_descriptor *ep;
627         struct usb_cdc_dmm_desc *dmhd;
628         u8 *buffer = intf->altsetting->extra;
629         int buflen = intf->altsetting->extralen;
630         u16 maxcom = 0;
631
632         if (!buffer)
633                 goto out;
634
635         while (buflen > 2) {
636                 if (buffer [1] != USB_DT_CS_INTERFACE) {
637                         dev_err(&intf->dev, "skipping garbage\n");
638                         goto next_desc;
639                 }
640
641                 switch (buffer [2]) {
642                 case USB_CDC_HEADER_TYPE:
643                         break;
644                 case USB_CDC_DMM_TYPE:
645                         dmhd = (struct usb_cdc_dmm_desc *)buffer;
646                         maxcom = le16_to_cpu(dmhd->wMaxCommand);
647                         dev_dbg(&intf->dev,
648                                 "Finding maximum buffer length: %d", maxcom);
649                         break;
650                 default:
651                         dev_err(&intf->dev,
652                                 "Ignoring extra header, type %d, length %d\n",
653                                 buffer[2], buffer[0]);
654                         break;
655                 }
656 next_desc:
657                 buflen -= buffer[0];
658                 buffer += buffer[0];
659         }
660
661         rv = -ENOMEM;
662         desc = kzalloc(sizeof(struct wdm_device), GFP_KERNEL);
663         if (!desc)
664                 goto out;
665         mutex_init(&desc->lock);
666         spin_lock_init(&desc->iuspin);
667         init_waitqueue_head(&desc->wait);
668         desc->wMaxCommand = maxcom;
669         /* this will be expanded and needed in hardware endianness */
670         desc->inum = cpu_to_le16((u16)intf->cur_altsetting->desc.bInterfaceNumber);
671         desc->intf = intf;
672         INIT_WORK(&desc->rxwork, wdm_rxwork);
673
674         rv = -EINVAL;
675         iface = intf->cur_altsetting;
676         if (iface->desc.bNumEndpoints != 1)
677                 goto err;
678         ep = &iface->endpoint[0].desc;
679         if (!ep || !usb_endpoint_is_int_in(ep))
680                 goto err;
681
682         desc->wMaxPacketSize = le16_to_cpu(ep->wMaxPacketSize);
683         desc->bMaxPacketSize0 = udev->descriptor.bMaxPacketSize0;
684
685         desc->orq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
686         if (!desc->orq)
687                 goto err;
688         desc->irq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
689         if (!desc->irq)
690                 goto err;
691
692         desc->validity = usb_alloc_urb(0, GFP_KERNEL);
693         if (!desc->validity)
694                 goto err;
695
696         desc->response = usb_alloc_urb(0, GFP_KERNEL);
697         if (!desc->response)
698                 goto err;
699
700         desc->command = usb_alloc_urb(0, GFP_KERNEL);
701         if (!desc->command)
702                 goto err;
703
704         desc->ubuf = kmalloc(desc->wMaxCommand, GFP_KERNEL);
705         if (!desc->ubuf)
706                 goto err;
707
708         desc->sbuf = usb_buffer_alloc(interface_to_usbdev(intf),
709                                         desc->wMaxPacketSize,
710                                         GFP_KERNEL,
711                                         &desc->validity->transfer_dma);
712         if (!desc->sbuf)
713                 goto err;
714
715         desc->inbuf = usb_buffer_alloc(interface_to_usbdev(intf),
716                                         desc->bMaxPacketSize0,
717                                         GFP_KERNEL,
718                                         &desc->response->transfer_dma);
719         if (!desc->inbuf)
720                 goto err2;
721
722         usb_fill_int_urb(
723                 desc->validity,
724                 interface_to_usbdev(intf),
725                 usb_rcvintpipe(interface_to_usbdev(intf), ep->bEndpointAddress),
726                 desc->sbuf,
727                 desc->wMaxPacketSize,
728                 wdm_int_callback,
729                 desc,
730                 ep->bInterval
731         );
732         desc->validity->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
733
734         usb_set_intfdata(intf, desc);
735         rv = usb_register_dev(intf, &wdm_class);
736         if (rv < 0)
737                 goto err3;
738         else
739                 dev_info(&intf->dev, "cdc-wdm%d: USB WDM device\n",
740                         intf->minor - WDM_MINOR_BASE);
741 out:
742         return rv;
743 err3:
744         usb_set_intfdata(intf, NULL);
745         usb_buffer_free(interface_to_usbdev(desc->intf),
746                         desc->bMaxPacketSize0,
747                         desc->inbuf,
748                         desc->response->transfer_dma);
749 err2:
750         usb_buffer_free(interface_to_usbdev(desc->intf),
751                         desc->wMaxPacketSize,
752                         desc->sbuf,
753                         desc->validity->transfer_dma);
754 err:
755         free_urbs(desc);
756         kfree(desc->ubuf);
757         kfree(desc->orq);
758         kfree(desc->irq);
759         kfree(desc);
760         return rv;
761 }
762
763 static void wdm_disconnect(struct usb_interface *intf)
764 {
765         struct wdm_device *desc;
766         unsigned long flags;
767
768         usb_deregister_dev(intf, &wdm_class);
769         mutex_lock(&wdm_mutex);
770         desc = usb_get_intfdata(intf);
771
772         /* the spinlock makes sure no new urbs are generated in the callbacks */
773         spin_lock_irqsave(&desc->iuspin, flags);
774         set_bit(WDM_DISCONNECTING, &desc->flags);
775         set_bit(WDM_READ, &desc->flags);
776         /* to terminate pending flushes */
777         clear_bit(WDM_IN_USE, &desc->flags);
778         spin_unlock_irqrestore(&desc->iuspin, flags);
779         mutex_lock(&desc->lock);
780         kill_urbs(desc);
781         cancel_work_sync(&desc->rxwork);
782         mutex_unlock(&desc->lock);
783         wake_up_all(&desc->wait);
784         if (!desc->count)
785                 cleanup(desc);
786         mutex_unlock(&wdm_mutex);
787 }
788
789 #ifdef CONFIG_PM
790 static int wdm_suspend(struct usb_interface *intf, pm_message_t message)
791 {
792         struct wdm_device *desc = usb_get_intfdata(intf);
793         int rv = 0;
794
795         dev_dbg(&desc->intf->dev, "wdm%d_suspend\n", intf->minor);
796
797         /* if this is an autosuspend the caller does the locking */
798         if (!(message.event & PM_EVENT_AUTO))
799                 mutex_lock(&desc->lock);
800         spin_lock_irq(&desc->iuspin);
801
802         if ((message.event & PM_EVENT_AUTO) &&
803                         (test_bit(WDM_IN_USE, &desc->flags)
804                         || test_bit(WDM_RESPONDING, &desc->flags))) {
805                 spin_unlock_irq(&desc->iuspin);
806                 rv = -EBUSY;
807         } else {
808
809                 set_bit(WDM_SUSPENDING, &desc->flags);
810                 spin_unlock_irq(&desc->iuspin);
811                 /* callback submits work - order is essential */
812                 kill_urbs(desc);
813                 cancel_work_sync(&desc->rxwork);
814         }
815         if (!(message.event & PM_EVENT_AUTO))
816                 mutex_unlock(&desc->lock);
817
818         return rv;
819 }
820 #endif
821
822 static int recover_from_urb_loss(struct wdm_device *desc)
823 {
824         int rv = 0;
825
826         if (desc->count) {
827                 rv = usb_submit_urb(desc->validity, GFP_NOIO);
828                 if (rv < 0)
829                         dev_err(&desc->intf->dev,
830                                 "Error resume submitting int urb - %d\n", rv);
831         }
832         return rv;
833 }
834
835 #ifdef CONFIG_PM
836 static int wdm_resume(struct usb_interface *intf)
837 {
838         struct wdm_device *desc = usb_get_intfdata(intf);
839         int rv;
840
841         dev_dbg(&desc->intf->dev, "wdm%d_resume\n", intf->minor);
842
843         clear_bit(WDM_SUSPENDING, &desc->flags);
844         rv = recover_from_urb_loss(desc);
845
846         return rv;
847 }
848 #endif
849
850 static int wdm_pre_reset(struct usb_interface *intf)
851 {
852         struct wdm_device *desc = usb_get_intfdata(intf);
853
854         mutex_lock(&desc->lock);
855         return 0;
856 }
857
858 static int wdm_post_reset(struct usb_interface *intf)
859 {
860         struct wdm_device *desc = usb_get_intfdata(intf);
861         int rv;
862
863         rv = recover_from_urb_loss(desc);
864         mutex_unlock(&desc->lock);
865         return 0;
866 }
867
868 static struct usb_driver wdm_driver = {
869         .name =         "cdc_wdm",
870         .probe =        wdm_probe,
871         .disconnect =   wdm_disconnect,
872 #ifdef CONFIG_PM
873         .suspend =      wdm_suspend,
874         .resume =       wdm_resume,
875         .reset_resume = wdm_resume,
876 #endif
877         .pre_reset =    wdm_pre_reset,
878         .post_reset =   wdm_post_reset,
879         .id_table =     wdm_ids,
880         .supports_autosuspend = 1,
881 };
882
883 /* --- low level module stuff --- */
884
885 static int __init wdm_init(void)
886 {
887         int rv;
888
889         rv = usb_register(&wdm_driver);
890
891         return rv;
892 }
893
894 static void __exit wdm_exit(void)
895 {
896         usb_deregister(&wdm_driver);
897 }
898
899 module_init(wdm_init);
900 module_exit(wdm_exit);
901
902 MODULE_AUTHOR(DRIVER_AUTHOR);
903 MODULE_DESCRIPTION(DRIVER_DESC);
904 MODULE_LICENSE("GPL");